We know that the news on artificial sweeteners can leave a bitter taste in your mouth. First people were afraid that saccharine causes cancer. (We now know there’s no danger, unless you’re eating dinosaur-sized portions of Sweet’N Low daily.) Then it was revealed that no-calorie sweeteners can make you crave real sugar and lead to weight gain. (That’s true.) And now there’s another piece of not-so-sweet news: Eating and drinking artificially sweetened foods and beverages may actually change the bacteria in your gut and make it harder for your body to process real sugar.This is getting complicated.

“It might be hard to swallow the notion that no-calorie sweeteners are as bad as sugar (which we know is a health and beauty buster in many ways), but it’s time to give them up.”

A September 2014 study in the journal Nature, testing a few humans and many mouse subjects, found that consumption of large amounts—equivalent to the daily maximum set by the FDA—of non-caloric artificial sweeteners, including sucralose (Splenda), saccharine (Sweet‘N Low) and aspartame (Equal), leads to glucose intolerance, or the inability of the body to properly take sugar from your blood stream into your cells. Glucose intolerance is a metabolic dysfunction associated with obesity, is a precursor to type 2 diabetes, and causes dysfunction of your proteins—like the decreased ability of your hemoglobin to release oxygen to your cells.The researchers dug deeper and discovered what seems to be a—if not the—reason. Somehow, these artificial sweeteners were changing the complex balance of bacteria in the gut, which can have major effects on metabolism (not to mention a whole host of other functions). That change in bacteria produced something (most likely a protein) you absorb into your blood that changed your ability to use insulin normally. Those changes made four of the seven healthy human subjects more intolerant to glucose, that is, to real sugar.So if you didn’t have any problem metabolizing sugar before you got hooked on diet soda, you might afterward.The bottom line: It might be hard to swallow the notion that no-calorie sweeteners are as bad as sugar (which we know is a health and beauty buster in many ways), but it’s time to give them up. You can wean yourself off slowly—half a packet in your coffee this week, a quarter of a packet the week after, and so on—and eventually you won’t miss them anymore. And if you feel the need for something sweet, go for either a very tiny bit of the real stuff, a Stevia leaf, or better yet of a spice like cinnamon.MORE: Coconut Water: Not a Super-Drink After All